Pump



c. G. HoLT June l0, 1930.

. PUMP Filed Oct. 2, 1926 5 1 21 w J 3 H A 11 111 111 111 1111 111.. 1111 1 11 1J M M 111 8 l 1 'l ll n l 3 2. l M a/a 1 9 7 7 l! 1 M 2 M 2 M 11 1v T1111 1 7 E .w. 11 1 1 n l 1 111 1 1111 2 *M l 11.1.1 l al 1 11 I1 2 6 3 7. l m.\ 7 n 7 4 5 Hf/u Z 2 2 6 ,1. M B W .d u 6 Pv 2 1 .o M @Q 5 0 0 W 1 M 2 J Z 2. A f 92 m 9 6 0 f u n 2 7 Patented June 10, 1930 PATEN'T OFFICE CLAUDE G. HOLT, OF ST. JOHNS STATION, MISSOURI PUMP Application filed October 2, 1926.

ing each stroke of the ordinary pump, the.

fluid entering the cylinder flows toward the piston, and the incoming fluid moves at substantially the same speed and. in the same direction as the piston. At the beginning of each stroke there is a sudden reversal in the direction of the flow of this fluid. The

1-5 incoming fluid tending to move onward in response to momentum must be stopped and then moved in the opposite direction. This reversal in the ordinary double-acting pump not only requires a sudden increase in power, but it also causes shocks in the pumping mechanism and results in very irregular pulsations usually requiring an air chamber as a cushion which only partly compensates for the various undesirable effects of the sudden reversals of the fluid in the pump.

One of the objects of the present invention is to produce a double-acting pump wherein these reversals are eliminated by the coaction of elements which cause a substantlally continuous progressive flow at each side of the piston. In other words, the fluid passes through the pump without reversing the direction of liow at either side of the piston. The momentum of the incoming fluid tends to move it lengthwise of the cylinder and toward the exhaust port, and when the piston motion is reversed the fluid is pushed in the same direction, so the pump does not require an added impulse to 4b overcome the momentum or to reverse the flow of the incoming liquid.

`As a consequence, I have eliminated various disadvantages that ordinarily result from sudden reversals of the fluid in the cylinder 45 of a double-acting pump. Less power is required to operate the pump; there are no severe destructive shocks at the beginning of each stroke; the ordinary air chamber may be dispensed with, and the fluid is delivered in a substantially uniform stream. Actual Serial No. 139,087.

experience has shown that the liquid dis charged in response to each stroke of the piston is greater than the displacement of the piston.

A further object is to produce a pump having a double piston with the piston elements separated from each other to form a passageway through which the fluid flows from an inlet to an exhaust port. The incoming fluid preferably passes one of these piston elements while the other piston element is used to discharge fluid from the cylinder, and the parts are preferably so arranged that the incoming liquid moves in a direction opposite to the piston movement, so as to avoid a reversal of the liquid to be discharged when the piston is reversed.

With the foregoing and other objects in I view, the invention comprises the novel construction, combination and arrangement of parts hereinafter more specifically described and illustrated in the accompanying drawings, wherein is shown the preferred embodiment of the invention. However, it is to be understood that the invention comprehends changes, variations and modifications which come within the scope of the claim hereunto appended.

Fig I is a longitudinal section of the dev1ce constructed in accordance with my invention.

Fig. II is a section taken approximately through the center of Fig. I, with some of the elements shown in elevation.

Fig. III is a section taken on line j IIL-III, Fig. I.

l designates an inner cylinder held within the outer cylinder 2 by means of webs 3, said outer cylinder 2 being provided with heads 4 and 5 both apertured to receive screw bolts 6 which connect the heads and force them onto gaskets 7 at the ends of the cylinders. Operating in said cylinder l is the double piston 8, said inner cylinder l,V being also provided with check valves 9 and an inlet port 10.

Integrally cast with the head 5 is an externally threaded collar 11 extending outward therefrom, on which is a screwed ring 12 which engages a iange on a gland 13 to force the same against packing 14.

Integrally cast with the head 5 is the inwardly projecting tube 15, drilled, tapered and threaded as shown in F ig. I. The upper check valve 9 includes a conical collar 16, preferably of rubber, having its small end rigidly clamped about the tapered nportion of the tube 15 by means of a tapered sleeve 17 engaged by a nut 17 on the threaded end of the tube 15. `he large end of the i'iexible rubber collar 16 yieldingly engages the inner face of cylinder 1, the whole acting as a check valve.

Integrally cast with the head 4 and extending inwardly therefrom is the tubular ymember 18 tapered `and threaded as shown in Fig. I. The lower-check valve 9includes a conical collar 19, also preferably of rubfber, rig-idly clamped about the tapered por- -tionf of said tubular member 18 .by means of fa -tapered sleeve 2O engaged by a nut l2O. -The largeend of -said rubber collar 19 yield- -ingly engages the inner face of the cylinder 1, the Vwhole also vacting as a check valve.

The lower portion of the tubular member `18ris provided with apertures 21. The .head .4 is provided with a discharge pipe 22 fthrough which fluid passes from the :aper- .tures.21.

'Ihe double piston 8 comprises a .pair of oppositely disposed conical collars 24 made of-.rubber yor other suitable iexible material, the ylarge ends of said collars being 4in contact -with the inner face of the Vcylinder 1, and adapted to overlap the relatively small ends of the collars 16 and 19, respectively. The means vfor securing thesefdexible collars includes a pair of inner tapering Amembers 25 .and 26 engaging inner faces of said collars at the small ends thereof, and v.awpair of -outer tapering members 27 and 28 contacting with the `outer lfaces .of said collars. The member 27 is provided with a tubular extension 29 engaging the small end of the tapering member 28. The inner tapering .members are connected by means of la screw 30 having a head engaging a shoulder on the member 26 and a vthreaded portion screwed into the member 25. The screw 30 can be adjusted to force the inner .tapering members 25 and 26 toward each other, thereby clamping the small end portions of `the flexible collars v.between said Ainner tapering members and the outer taperfing members 27 and 28.

The large ends of .the conical rubber vcollars yieldingly engage the inner face of the .cylinder 1 `to serve as piston members and also .to act as check valves.

31 designates va Ypiston vrod extending through the stuffing box in the cylinder lhead 'and having an enlarged -end 82 loosely mounted inthe tapered member-25 and .secured by means of a short screw :33. The

piston rod is also loosely secured in the stuling box, and the gland 13 has a tapered opening to permit lateral displacement of the piston rod.

In Fig. II the arrows shown by full lines indicate the directions in which the Huid Hows when the piston lmoves downwardly, and the Aarrows shown by `'dotted y:lines indicate the directions when the piston moves upwardly. In operation fluid venters the inlet port 10. The piston traveling downward drives the Huid before it past the lower check valve .9, v thence through the apertures 21 and out the discharge pipe 22. While this is occurring the vacuumcreated in lthe chamber at -tlie'other yend of the .cylinder caused gby the .downward `stroke-of ithe piston .draws theiiuid past the upper check valve .member24 .of thepiston into said chamber. On `the upward stroke the functions are re.- versed, vthefluid being forced Ipast the .upper kcheck valve y9, down through the annular lspace between the `two .cylinders zand out .through the apertures 21.

At the end of the `.downward stroke, .the piston momentarily stops .beforestarting upward again. However, the momentum of fthe fluid, entering the pump, tends ,to cause .the iuid Eto Vflow past ithe upper check .valve 2 4 :on .the piston v and also past check valve ,9 in the .upper .part .of the cylinder, even .before 4the piston starts .on its return stroke, ,this being possible because both of these .valves open in the same direction. That the pump, in actual test, delivered more -iiuid than the actual displacement volume of the piston substantiates the above.

v It .will now be apparent that -the Aincorning liquid moves ina direction opposite to the :piston movement, and that this avoids Ia reversal ofthe liquid to Vbe discharged when the ,piston is reversed.

In vthe pump I have shown to illustrate ,one form .of the invention .the -port 10 between Lthe valve .elements 24 .off ,the piston Y serves as an linlet port, Vand the Ycheck valves 9 vlie in .the exhaust ports, but it 4is to be understood that the invention is not limited to this arrangement. By merely reversingthe .check valve .elements 9 and 24, the port V10 =wilrl become .the =exhaust port and the ports `atthe. ends of .cylinder 1 will be thefinlet ports.

y.I claim:

In a double-acting pump, a ,cylinder `having an inlet port, .a double piston in said cylinder, Isaid cylinder ,being .provided with yoppositely disposed flexible .conical check valves llocated at its ends and contacting .with'the Vinner face of the cylinder, said pis- Vitonbeing,provided with oppositely disposed flexible conicalfcheclr valves contacting with the inner face .of said cylinder at opposite vsides olf said ,inlet port and cooperating 

